pvlib.singlediode.estimate_voc¶

pvlib.singlediode.estimate_voc(photocurrent, saturation_current, nNsVth)[source]

Rough estimate of open circuit voltage useful for bounding searches for i of v when using singlediode().

Parameters
• photocurrent (numeric) – photo-generated current [A]

• saturation_current (numeric) – diode reverse saturation current [A]

• nNsVth (numeric) – product of thermal voltage Vth [V], diode ideality factor n, and number of series cells Ns

Returns

numeric – rough estimate of open circuit voltage [V]

Notes

Calculating the open circuit voltage, $$V_{oc}$$, of an ideal device with infinite shunt resistance, $$R_{sh} \to \infty$$, and zero series resistance, $$R_s = 0$$, yields the following equation [1]. As an estimate of $$V_{oc}$$ it is useful as an upper bound for the bisection method.

$V_{oc, est}=n Ns V_{th} \log \left( \frac{I_L}{I_0} + 1 \right)$
1

http://www.pveducation.org/pvcdrom/open-circuit-voltage